1. Field
Methods and apparatuses consistent with exemplary embodiments relate to an optical system and an image projecting apparatus using the same, and more particularly, to an optical system which is adapted to project light onto a big screen in a small projecting space, and an image projecting apparatus using the same.
2. Description of the Related Art
With the development of the information industry, devices to meet the growing demand for big screens, such as an image projecting apparatus using a light source, have become popular.
In general, an image projecting apparatus includes a screen and a projector to enlarge and project an image onto the screen. Particularly, in order to form a projected image on the screen, the image projecting apparatus is required to have a constant projection distance.
As the projection distance becomes longer, the image generated at the projector is more likely to be blocked by an obstacle or a user midway between the projector and the screen, and there is a problem that light projected from the projector enters users' eyes.
In order to solve these problems, short distance projectors and ultra short projectors, having short projection distances, have recently been developed. The short distance projector has a projection distance of about 60-70 cm between the projector and the screen, and the ultra short projector has a projection distance of about 30-50 cm.
However, as the projection distance becomes shorter, there is a problem that additional functions, such as a zoom function, are not supported due to the size and the projection distance of the projector.